app/views/layouts/_twitter_card.html.erb
<meta name="twitter:card" content="summary">
<meta name="twitter:site" content="@holderdeord">
<meta name="twitter:title" content="<%= metadata[:title] %>">
<meta name="twitter:description" content="<%= metadata[:description] %>">
<meta name="twitter:creator" content="@holderdeord">
<meta name="twitter:image:src" content="<%= metadata[:image] %>">
<meta name="twitter:image" content="<%= metadata[:image] %>">
<meta name="twitter:domain" content="holderdeord.no">